The invention relates generally to powered tensioning tools, and more particularly to powered tensioning tools having collar actuated air valves and methods therefor.
Powered tensioning tools are known generally and used widely to tension strap about a load. These tools comprise generally a feed wheel protruding from a gear housing of the tool for engaging and tensioning strap disposed between the feed wheel and a base plate, or foot, of the tool. The feed wheel is driven generally by an air motor disposed in a drive housing coupled to the gear housing, and a pneumatic valve controls the supply of compressed air to the air motor from an air line coupled to the drive housing.
In some tensioning tools, disclosed for example in U.S. Pat. No. 3,028,885 entitled "Power Strap Tensioning Tool", the pneumatic valve is actuated by depressing a button operated switch protruding from the drive housing. In other tensioning tools, disclosed for example in U.S. Pat. No. 3,249,131 entitled "Power Strap Tensioning Tool", the air motor is operated with a ring, or collar, valve actuator rotatably disposed about the drive housing. The collar valve actuator is generally rotatable back and forth over a small angular interval to open and close the pneumatic valve, and thus to control the air motor.
Prior art FIG. 4 of the present patent application illustrates more particularly the actuation of a pneumatic, or air, valve 10 in a housing 20 of a strap tensioning tool by a collar 30 rotatably coupled thereto. The collar 30 is rotatable relative to the housing 20 back and forth over some angular interval, which is limited by a pin 22 protruding radially from the housing 20 into a recess 32 of the collar. The pin 22 is engageable with stops 34 and 36 on opposing ends of the recess 32 upon rotation of the collar 30. The valve 10 includes a valve stem 16 biased by a spring 12 so that an actuator portion 14 thereof is biased to protrude from the housing 20 and into engagement with an inner portion of the collar 30. In a first position of the collar 30, illustrated in FIG. 4, the spring 12 biases the valve stem 16 into a tapered recess 38 of the collar 30 to open the supply of compressed air from an air line fitting 24 on the housing 20 to the air motor. When the collar 30 is rotated counter-clockwise relative to the housing 20, the tapered recess 38 thereof engages and depresses the actuator portion 14 of the valve stem against the bias of the spring 12 to close the supply of compressed air at the o-ring seal 19. The collar of known tensioning tools however must be rotated manually relative to the housing to actuate the valve that opens and closes the supply of compressed air.
The present invention is drawn toward advancements in the art of collar actuated valve assemblies useable in powered tensioning tools.
An object of the invention is to provide novel collar actuated valve assemblies for powered tensioning tools and combinations thereof that overcome problems in the art.
Another object of the invention is to provide novel collar actuated valve assemblies for powered tensioning tools and combinations thereof that are biased in a position that terminates the supply of air to an air motor of the tool.
A more particular object of the invention is to provide novel collar actuatable air valves useable in air powered strap tensioning tools, and combinations thereof, comprising generally a collar rotatably coupled to a housing, and an air valve disposed at least partially in the housing and having an actuator portion biased to protrude therefrom and into engagement with an actuator surface of the collar. A collar biasing member rotatably biases the collar to close the air valve, whereby the collar is rotatable against the bias of the collar biasing member to open the air valve.
Another more particular object of the invention is to provide novel methods for operating air powered strap tensioning tools comprising generally supplying air to an air valve disposed at least partially in a housing of the tool, biasing an actuator portion of the air valve to protrude from the housing and into engagement with a collar rotatably coupled to the housing, and rotatably biasing the collar to close the air valve, whereby the collar is rotatable manually against the bias to open the air valve.
These and other objects, aspects, features and advantages of the present invention will become more fully apparent upon careful consideration of the following Detailed Description of the Invention and the accompanying Drawings, which may be disproportionate for ease of understanding, wherein like structure and steps are referenced generally by corresponding numerals and indicators.